Intake manifold for v engines and the like



`lune 27, 1961 Filed Oct. l. 1954 8 Sheets-Sheet 1 INVENTo .si E i.,.rz'rz 47'] June 27, 1961 w. E. DRINKARD x-:rAL 2,989,956

INTAKE MANIFOLD FOR v ENGINES AND THE LIKE Filed Oct. l. 1954 8Sheets-Sheet 2 June 27, 1961 w. E. DRINKARD ETAL 2,989,956

INTAKE MANIFOLD FOR v ENGINES AND THE LIKE Filed Oct. 1. 1954 8Sheets-Sheet. 5

June 27, 196,1 w. E. DRINKARD EVAL 2,989,956

INTAKE MANIFOLD FOR v ENGINES AND THE LIKE 8 Sheets-Sheet 4 FiledOct. 1. 1954 w. E. DRINKARD ETAL 2,989,956

INTAKE MANIFOLD FOR v ENGINES AND THE LIKE June 27, 1961 8 Sheets-Sheet5 Filed OCT.. 1. 1954 l INVENToR June 27, 1961 w. E. DRINKARD ETAL2,989,956

INTAKE MANIFOLD EoR v ENGINES AND THE LIKE Filed 061'.. l. 1954 8lSWts-Sheet 6 zz w. WZ /M m i /w www June 27, 1961 w. E. DRINKARD ErAL2,989,956

INTAKE MANIFOLD FOR v ENGINES AND THE LIKE Filed Oct. l. 1954 June 27,1961 w. E. DRINKARD ETAL 2,989,956

INTAKE MANIFOLD PoR v ENGINES AND THE LIKE Filed Oct. l, 1954 8Sheets-Sheet 8 l-H. f

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IN VEN TORS 34 E. l E MEI/m fraz/VII@ tentant;aenaiaafiraient'sealantafneemt; numbers. Qf.; cylinders and will'tadant -therrlsliesinthe y a :Filed oct. 1', 19s4,`ser.aNe. 459,168. I a 2s claims@v (01.-.12s-,122)V This invention -,.re12\tts t9, t engines having opposedlbanksV engines.4 It particularly-concern A K. marlifrildv YStructure., 4fQrV; engrle fwhicrhr factory distribution of the airfuelmixture to K fAthe engine; .which .is easy' tQpCasLaW and which can utilizeexhaustygaS-.Qr-,liau t spotheating.'n 1 a y i Manifold Astructures.',currentlyffmade for? V nginesvY 1, 'i fnector means alsomakesgpossiblY Yequah,distancesrom use there dssirsxofa single Qr-PLr'I-ralty,Otrcarburetotst each of one or"'1nore barrels and withoutany changegn crqrrrplratiorrarrthe nduitsystemf `vii-the manifoldeiotherthan -tO- prQYdea YCorrect-rirlrrrber*f irrtakegfrrisers which,advantageously may all be of the same height, a fact 0f iorrsiderableimportance. :from the .fstandpoi tribufi9r1ar1d-ma9bining-i. t a Y heSingleplaneaarrangemcn COIldlll 0,1175

thezpeint 0r V:peints rafapririspalglairY fuel; Supplyatm the Cylinders,fMoreQver, fit; is foundthat fwithfmriltiplecar-: huretienaQQr-alevelirrterwruleetion;afy the conduitgroupsf also KVmakes.,possible.,.betterA controlY of athe, liquid fuelemploy a system ofinterleavedairffuel-conduitsdesigtied to provide good-,distribution toAlthe enginelcylinders f1-,oniv a carburetor 'having oneor.-I morebalrels. jWhileproduiV tive of good'vresults, suchamani'folds'rrequrecomplexgand relatively heavy castings, when,-, as generallyJ Visa-the 7case,J they areamade in onepiece.y onsiderable" dicult'-jsand; core workis necessaryinrmakingfthe `patterns;and''in casting) and this Y 'isVcostly. afgMoreoyen .the` linterleaved character of the; conduitsproducesga manifold fhaving a rather high silhouette. Vsuch that rY-thefmanifoldk doesnot,` lenditself lto Vapplicationsywheregheightspace-atfaf premium or ,tot tit into marine: applications: ywherertheanfglie ofgrinstallation gof; the: i engine vis oftentimes g'regitiand,4

height space available is limited. The highsilhouettev of 4theconventional. iconsnfuctionrhas :also :made`A itggdicult insomeiinstancesa'to replacealitieengine?,installationsJ invention may beadapted tonie-casting. f 1

applicable to manifold constructions-fvyhe're ia= multiple;barrelgsupply Carburetor feeds :totheamidpoint 'offs the interconnectionand .-whereithe floorof `the,interconnetz't'ore may bei `designed to,provide suitablerliquidtfuel; datnmingf means,Thesingleplaneconstruction aforesaidf facilitates;v theu/se ofiwiderflatsectionsLinntheconduiksystem -withae out excessive turn restrictionsand by propen design and; selectionv lof; l the casting lsplitli'ne themanifoldsvv of our ria-The isinjgle planeacharacter of -therconditi'andlconnections of our manifolds moreover pertnts the'segregation of hotspotheating to ftheprimary distribution z'oneofathe airfuel .mixtureatthe ,intake i risers :thusf' avoiding funde-: sirableVV heat-ing1 ofanyjo'neconduitl orV heating of 5 one :toi the exclusion4 :of zaanother;where suchxis. notgspecicallys desired and may be conveniently adaptedto `either exhaust:-` gasg'orliquidcoolant-lieatingiV 12. .if

provide.; in engines-ofzthe itypeidescribed 'intake E'mani-j` with atvengine. '1r-In many caseslgit'has been necessary; l

fuelconduits Yoffrdirectly oppositeacylindersintocgroups; if preferablynot exceeding four conduits, with thegcon-Iy duits of each Lgroup inacomxnongvertical plane andfconvergingrat a common intersection,;andbyarrangingthesev groups ina substantially common vertical planeLVandinf:- terconnecting the groups at their intersectionsbyrfcontluit:` means inthe same planewasrthe conduitsof.4 theigroupsg:ThusA in the; Casfof 2111v S-cylindera-Vfengineeforexample' themanifldbrsrrches will berransed initwoaconnected Sets '.Of'Xformatirrrarrdfwill thrrspreserlt a-sirrglenlans:

connected XX construction.

By -reaSQrr ofthis 1ro-relsqrrstrrrctorrempigyine a'fsnl plane` or.floor level interconnectionjo the onduitsfjthe;

niarrifels. @flair jiniemirr willhere e mwen airen restriction thanmanifolds `xivherfce, Aa struction is.lemployed;.-Will-apresentvaaldistinct j fd 'antage inthe contro o constructionsv ysubrstarntialitherjmanifldsivillrb trrrarrrf@ 'asha'nd accelerator pamp requirements;,wilt leadithjefasetvfe'st. toi d fuelftrabs'suchlthat fold;of singlelplaner-'character `throughoutits airfuelfsconflgduit systemtfacilitatingthe attainmentl of alowesilhouetw andflow air-110Wrestriction;A

intheprevious' object,A in'` which f the vconduits have Lacommonfloorlevel andv may; for instance'iby da improved'liquid-fuelcontrol.; i gf: L

Arfurtheriobject is toprovide a-man'ifold struc engines having opposedfcylinder Abanks. whereih'ithef cori-T duti branches of .thefairfuelfconduitsystem' which' fe'edl` l Siderable Ser/irre 0f,metalfrarrdfweiit arri; "rlfrfrr irri a gen'erally common'lhorizontalplane Vtherewith'fand prvider passages 'of substantiallyequalflengt ein th' risente the-iint'akevawe port/sof the enginef';suufonefb1enmanovre man@ n s naar. sefforthin` theprevios"'objects"which*are lparticularly .Sti11 1. another abject iS-10,providea: Sirrpl; @irre-'piede manifold structure'` of `thegtypes; inthe :foregoing objects:

L to which either exhaust heat or liquid coolantrheatingnf;

y A vis"engineshavingfau"tha-air-fuarcndn *i common Aplan p r f re,em-Bodi the -risenLdistribution:fzonecuiiiayyrbe applied ifo VVengineWarm-upf" ffii: Y :if a", A further sliecific objectis 5to provid alrnanifold' (for i1L afgenerallyf X'X andv arranged -tofsimiilat'e a:lconn f L ""Othe'robjects and* advantages be apparent from .111@150119YV'8 engines of current manufacture, reference being had to theaccompanying drawings wherein:

FIGURE 1 is an end elevational view partly in section of an overheadvalve V engine of current manufacture embodying the novel intakemanifold system of our invention and is shown provided with a singlebarrel downdraft carburetor and exhaust gas heating of the intake riserhot spot;

@FIGURE 2 is a plan View of the intake manifold shown in FIGURE 1 asapplied to an S-cylinder V engme;

FIGURE 3 is an end elevational view taken from the fan end of the engineand partlyV in section, of the intake manifold of FIGURE 2 illustratingthe single plane character of the air-fuel conduits;

FIGURE 4 is a longitudinal cross sectional elevation of the manifold ofFIGURE 2 through the intake riser and showing a portion of thecarburetor feeding the same, this section being taken at 4-4 of FIGURE2;

FIGURE 5 is a schematic view of an S-cylinder V engine of the type inFIGURE 1 and employing the manifold of FIGURE 2;

FIGURE 6 is a schematic view of an 8-cylinder V engine of the type shownin FIGURE 1 provided with the novel single plane XX manifold of ourinvention fed by a central single barrel carburetor and provided withmeans for heating the intake hot spot by the coolant uid of the engine;

FIGURE 7 is a plan View of the intake manifold employed in the engine ofFIGURE 6;

-LFIGURE 8 is a longitudinal side elevational view of the'manifold ofFIGURE 7;

FIGURE 9 is a cross sectional elevation taken at 9 9 of FIGURE 7 throughthe intake riser and -hot spot cornpartment of the manifold of FIGURE 7and showing a single barrel downdraft carburetor mounted on the intakeriser seat;

FIGURE l is a cross sectional elevational view taken longitudinally ofthe manifold of FIGURE 7 on the line 10-10 through the intake riser,primary air-fuel conduit and hot spot compartment, it illustrating theliquid coolant passages for heating the riser throat and thedistribution zone of the primary air-fuel passage as well as showing thevreturn conduit for the liquid coolant;

FIGURE 1l is'a cross sectional view taken at 11-11 of FIGURE 7 showingthe air and steam bleed passages for the liquid coolant hot spot heatingsystem;

f FIGURE 1,2 is a cross sectional view taken at 12-12 of FIGURE 7Vthrough a pair of branches of the air-fuel mixture feeding system andthrough one of the bleed passages and showing the cross-sectional shapethereof;

FIGURE 13 is a plan View of the intake manifold of our invention ofFIGURES 6 and 7 modiiied to provide for feeding of air-fuel mixture by adual carburetor and utilizing a floor dam liquid fuel control and amodified form of hot spot heating by the liquid coolant of the engine;

FIGURE 14 is an end elevational view of the manifold of FIGURE 13 brokenaway to show in section a portion of air-fuel passages and thedistribution zone at the intersection thereof;

FIGURE'IS is a transverse section of the manifold of FIGURE 13 taken at15-15 of FIGURE 13 through the dual intake riser primary distributionzone and hot spot compartment and showing the return passage for theliquid coolant;

FIGURE 16 is a longitudinal section taken at 16--16 of FIGURE 13 throughone of the intake risers and through the primary and secondarydistribution air-fuel zonesV and showing the hot spot compartmentpassages for heating the foregoing during warm-up;

FIGURE 17 is a transverse section taken at 17-17 of FIGURE 13 throughthe liquid coolant intake passages for the hot spot compartment;

FIGURE 18 is a schematic view of the manifold of our invention as shownin FIGURES 1, 2, and modilied to provide for feeding of the engine by apair of concentric downdraft carburetors with exhaust gas heatingapplied to each of the intake riser hot spots; and

FIGURE 19 is a further modification of the manifold of our invention ofFIGURES l, 2, and 5 providing for air-fuel feeding by three concentricdowndraft carburetors, only the central one of which has its intakeriser hot spot heated by exhaust gas of the engine.

Referring now to the drawings wherein similar numerals are used todesignate similar parts of the intake manifold structure and system ofour invention we have, as stated above, illustrated our invention as-applied to a water-cooled V-8 engine of current manufacture, Thisengine is provided with a so-called two-plane 90 crankshaft,hemispherical combustion chambers, and with suitable carburetionillustrated as of the downdraft type, FIGURES 1 and 5 for example,illustrating the use of a single barrel carburetor of the downdraft typearranged to provide substantially uniform distribution of air-fuelmixture to the cylinders of the opposite banks of the engine.

As seen in the drawings, especially FIGURES 1 and 5, the engine has twobanks 9 and 9a of cylinders 10, four in each bank, arranged at 90 in acylinder block 11 to which cylinder heads 12 and 12a are secured andprovided with hemispherical type combustion chambers 13 immediatelyabove each cylinder 10. The cylinders of each bank are preferablyaligned longitudinally of the engine and the cylinders of the oppositebanks are preferably offset longitudinally relative to each other.

For convenient reference, the cylinders of the left hand cylinder bank.which is to the left looking forward from the ywheel end of the engine,are numbered 1, 3, 5, and 7 respectively, starting such numbering at thefan end of the engine, and those of the right hand cylinder bank arenumbered 2, 4, 6, and 8 respectively, these numbers appearing integrallyof the cylinder representations in FIGURE 5.

Each cylinder is provided with a piston 14 reciprocable therein andoperatively connected to a crankshaft 15 by a connecting rod 16 andwrist pin 17. Crankshaft 15 may be of any of the conventional types, butpreferably is an inherently balanced shaft, for example, a 90 two-planecrankshaft having double crank throws arranged 90 apart.

The hemispherical combustion chambers 13 of the cylinders 10 are bypreference each provided with a single inlet opening or port 18 closedby an inlet valve 19 and with a smaller single exhaust outlet or port 20closed by an exhaust valve 21, these valves being arranged transverselyof the longitudinal axis 22 of the engine and at a substantial angle,for instance, 60 to each other, and preferably. on a great arc of thespherical segment forming the combustion chamber 13. As seen in FIGURE5, for instance, all of the inlet openings 18 are in longitudinalalignment and all of the exhaust openings 20 are similarly arranged.

f The inlet and exhaust valves of both banks of the engines are operablefrom a single camshaft 24 located above the crankshaft 15, the camshaftactuating suitable tappet mechanism associated with the push rods 25 and26 of the inlet and exhaust valve mechanisms respectively, which int-urn actuate respectively the inlet valve rocker arms 27 and exhaustvalve rocker arms 28, these rocker arms actuating in turn the normallyspring held closed valves 19 and 21.

lReferring now iirst to FIGURES l, 2, 3, 4, and 5, the intake manifoldof our invention which is designated by the numeral 29 generallycomprises left and right side mounting or flange portions 30, 32respectively, connected. by conduit means to be described with acarburetor mounting and jacketed air-fuel distribution or hot spotsection i generally referred to by the numeral 34.

Theside mounting portions 30, 32 extend longitudinally ofthe engine andhave-bottom faces 36, 37 respectively which converge downwardly towardeach other at an angle of about 120 and seat, as seen in FIGURE 1, uponthe inner similarly angled faces 38, 39 of the cylinder heads 12, 12arespectively, through intervening gaskets 40.

The jacketed air-fuel intake section 34 in FIGURE 2 is shown as agenerally central section having a top wall portion 41 (FIGURES l, 2,and 3) provided with a mounting pad 42 on which is secured by bolts 43with an intervening gasket means 44 and air-fuel supply device hereshown as a single barrel downdraft carburetor 45, although other typesupdraft, or downdraft, and with side or concentric air cleaners may beused.

The carburetor 45 has a vertical cylindrical barrel or passage 46 fromwhich gas or air-fuel mixture may be delivered to a relatively shortvertical intake riser or passage 48 on the axis 22 which opens throughthe pad 42 of the central section 34 t0 form a continuation of thebarrel 46. The amount of gas or air-fuel mixture delivered to the riser48 may be controlled by a throttle member 50 having a throttle blade 51located in the barrel 46 and adapted to assume predetermined positionstherein between fully open and fully closed throttle.

The intake riser 48 is preferably of cylindrical shape and intersectswith a generally horizontally extending primary conduit generallyreferred to by the numeral 52 of rectangular section which provides anair-fuel distribution zone 54 into which the riser 48 opens. The primaryconduit 52 has portions 56, 58 (FIGURE 2) extending on opposite sides ofthe riser 48 to secondary distribution zones 60, 62 respectively, thezone 60 being formed by the intersection of the primary conduit portion56 with a group or system of branch conduits 63, 64, 65, and 66 at theforward engine end of the manifold and the zone 62 being formed by theintersection of the primary conduit portion 58 with a second group orsystem of branch conduits 67, 68, 69, 70 at the rearward engine end ofthe manifold.

As seen in FIGURE 2, each of the aforesaid two groups of branch conduitsis arranged in a letter X and the two groups together form a connecteddouble X, being connected centrally longitudinally by the primaryconduit 52 and outwardly i.e., at the outer ends of the branch conduitsby the manifold mounting anges 30, 32.

The branch conduits 63, 64 of the forward group provides passages 72, 73respectively, which extend from the distribution zone 60 to openings 74,75 in the flange 32 Where they connect with the intake passages 76 forcylinders 2 and 4 of the right hand cylinder bank. Branch conduits 65,66 provide passages 78, 79 respectively extending from the same zone 60to openings 80, 81 in the flange 30 where they connect with the intakepassages 76 for cylinders 1 and 3 of the left hand bank. Similarly, thebranch conduits 67, 68 of the rearward group provide passages 82, 83which extend from the distribution zone 62 to openings S4, 85 in theflange 32 where they connect with intake passages 76 for the cylinders 6and 8 of the right hand bank and branch conduits 69, 70 provide passages86, 87 respectively extending from zone 62 to openings 88, 89 in theange 30 for connection with the intake passages 76 for cylinders 5 and 7of the left hand cylinder bank.

As seen in FIGURE 3, all of the branch air-fuel conduits 65, 66, 69, and70 on the left side of the intake manifold 29 of the engine are in thesame general horizontal plane i.e., if superimposed in that view theywould coincide and the same is true of the conduits 63, 64, 67, and 68at right side of the manifold, these being mirror images respectively ofthose on the left side. These conduits as shown in FIGURE 2 all extendobliquely with respect to the central axis 22 of the manifold and asstated in a generally horizontal plane transversely of the engine whichis also the plane of the primary conduit 52 and dip downwardly slightlyat their outer ends where they connect with the manifold mountingflanges 30, 32. The described conduit system vastly simplilies theproblem of 6 pattern making and casting. The pattern will be simple instructure and all cores will be interconnected and will have amplesupport at their outer ends so as to facilitate the obtaining of cleancastings with conduit walls of uniform thickness and thin as possible.The conduit arrangement, moreover, will produce a manifold of materiallyreduced weight and will facilitate the obtaining of a low silhouette, afactor of considerable importance in current motor vehicle design. Itwill also make pos-sible substantially equal distances between the riser48 and the intake ports 18 of the engine cylinders.

The hot spot section 34 of the intake manifold in FIG- URES l to 5includes transverse passage and chamber means connecting with the engineexhaust system for conducting exhaust gas of the engine into heattransfer relationship with the riser and its distribution chamber zone54 of the primary air-fuel conduit 52 for heating the air-fuel mixtureduring engine warmup. This is accomplished under control of a heat valve92 shown in FIG- URE 1 located in the exhaust pipe 93 between theexhaust manifold 94 of the right hand cylinder bank and the connectionof the pipe 93 with the exhaust pipe 95 connecting with the exhaustmanifold 96 of the left hand bank of the engine.

The section 34 comprises a central compartment or chamber 98 (seeFIGURES l, 2, 3) of generally U-shape transversely and elliptical inplan straddling and jacketing the sides and bottom of the primaryconduit 52 and distribution zone 54, and a pair of opposite offsetconduits 99 and 100 extending between the chamber 98 and the mountingflanges 30, 32 respectively, of the manifold.

As seen in FIGURE 2, the primary conduit 52 passes completely throughthe chamber 9S `and :the conduits 99 and 100 are somewhat narrower thanthe chamber 98 and are of rectangular section, these yconduits beingoifset from each other longitudinally of the manifold by reason of theoffset between vthe cylinder banks and making the construction of oneside of the manifold symmetrical with that of the other side. Theconduits 99 and 100 provide passages 101, 102 respectively terminatingin apertures 103, 104 in the flanges 30, 32 which passages conneet thechamber 98 with the exhaust crossover passages 105, 105a (FIGURES l and5) of the cylinder heads at said apertures 103, 104. The crossoverexhaust passages 105, 105a in turn connect with the exhaust manifolds 96and 94 respectively.

As seen in FIGURES 1 and 4, the bottom Wall 106 of the distributionchamber 54 of the primary conduit 52 and the bottom Wall 107 of thechamber 98 define the base of the U-shape of the chamber and the sidewalls 108, 109 of the conduit 52 (see FIGURE l) and the outer ellipticalwall 110 of the chamber 9S define the legs of the U chamber. I-t will benoted from FIGURE 4 that the space 111 between the walls 106 and 107 ofthe chambers 54 and 98 is of an elongated rectangular shape, suchproviding a cross-sectional area substantially equal to that of thepassages 101, 102 of the hot spot structure.

In operation of the engine, the exhaust gases will normally bedischarged by way of the exhaust manifolds 94, 96 and pipes 93, 95 to amain ourtlet pipe, not shown, at such time Ias the valve 92 is open andthere will be some slight movement of exhaust gases to the variouscrossover passages described above. During warmup, however, the valve 92will be closed and in these circumstances the hot exhaust gases of theright hand cylinder bank will be diverted through the crossover passage105a to the inlet passage 102 of the chamber 98 where the gases willstrike the wall 109 of the air-fuel distribution chamber 54 turned downand under the floor 106 of this chamber 54 and out the discharge passage101 and through the crossover passage 105 of the left hand cylinder bankto the exhaust manifold 96 and out the pipe 95. Accordingly, in thismovement of the exhaust gases the walls 106, 108 and 109 will be heatedby the exhaust gases and transfer their heat to the -air-fuel mixturefed 7 to 4the distribution chamber 54 by the carburetor 45. f

FIGURE 5 schematically shows for completeness the liquid coolant systemof the engine embodiment in FIG- URE 1 such being independent of theintake manifold in View of the use of exhaust gas hot spot heating. Asseen, a pump 120 circulates liquid coolant to the cylinder block 9 ofthe engine through conduits 122, 124 from which it passes to thecylinder heads 12, 12a through internal passages not shown, and isreturned to the pump by means of conduits 126, 128 under control of abellows-type valve 130. When the valve port 132 is closed, as shown,which is during engine warmup, the liquid coolant enters the valve bodystructure 133 and returns to the pump intake side by the bypass conduit134. When, however, port 132 of the valve 130 is open, the liquidcoolant flows past the port 132 and through a conduit 136 Ito the topside of the engine radiator 137 and down through the cells of theradiator returning to the intake side of the pump by a conduit 138.

FIGURE 5 also schematically shows the engine distributor timingmechanism 140 arranged to deliver current to re the spark plugs 142according to a firing order l, 2, 7, 5, 6, 3, 4, 8 which numeralsrepresent the cylinder members of the engine shown inside of thecylinder circles in FIGURE 5. It will be understood that other firingorders may be employed in connection with the manifold of thisinvention.

In FIGURES 6 to l2 inclusive, we have illustrated a V-8 engine having anintake manifold 29a utilizing the novel XX intake manifold of ourinvention in a form which provides heat transfer to the hot spot areacomprising the carburetor riser and primary distribution zone, by theliquid coolant of the engine. The arrangement broadly features amid-manifold liquid coolant compartment jacketing the riser and primaryair-fuel distribution conduit; a pair of offset transversely extendinginlet conduits providing passages connecting the opposite cylinder headswith the heating compartment; a central longitudinally extending liquidcoolant return passage; and air and steam bleed means between the latterand the cylinder heads of the engine, all as more particularly shown andclaimed in the `copending application of Philip M. Rothwell Serial No.447,805, filed August 4, 1954 and to which reference is made for any`essential structure omitted in this description. This feature ispossible of application to our novel XX manifold, without adverselyaffecting the basic simplicity of the XX manifold construction and itsadvantages.

Referring especially to FIGURES 7 to 9, -a liquid coolant heat transfercompartment 34a comprising a chamber 151 having a substantially U-shapeportion, straddles the bottom 106 and lateral sides 108, 109 of theprimary airfuel conduit 52 at the primary air-fuel distribution zone54-and rings the riser 48. Between the compartment 34a Land the mountingflanges 30, 32 respectively, are transverse offset liquid coolant inletconduits 152, 153 which provide passages 154, 155 leading from the legportions of the chamber 150 and terminate in apertures 156, 157coinciding with outlet passages 158, 159 of the water jackets orgalleries of the cylinder heads 12 and 12a respectively, intermediatethe middle cylinders 3 and 5 of the cylinder head 12 Iand intermediatethe middle cylinders 4 and 6 of the cylinder head 12a.

It will be evident from FIGURES 9 and l0 thast the hot liquid coolantentering the chamber 150 from the cylinder heads by Ithe inlet passages154, 155 not only transfers heat to the walls of the primary air-fuelconduit 5,2, but also iows around and transfers heatrto the wall 160 ofthe riser 48 at the annular liquid coolant space or gallery 161 (FIGURE10) connecting with the legs 162, 163 of the chamber 150. The liquidcoolant then discharges from the gallery 161 `into the chamber orpassage164 of aconduit 165 extending longitudinally of the manifoldonthe central axis 22thereof and immediately riser 48 from the above theprimary air-fuel conduit 52 with which it has a common wall 166 andreturns the liquid coolant to a valve housing 133 (see FIGURES 6 and 8)seated over a top aperture 167 of conduit 164 from which it passes tothe return side of the pump under control of a bellows-type valvelocated in this housing.

It will be evident from the schematic showing in FIG- URE 6 that whenthe valve 130 is open, the Warm liquid coolant flows past the valve port132 through the conduit 136 to the radiator 137 and back to the returnside of the pump by the lconduit 138 and that when the valve 130 isclosed, the liquid coolant bypasses the valve port 132, it thendischarging from the valve housing 133 to a bypass conduit 134connecting with the return side of the pump 120.

Air and steam bleed means in the form of conduits 169, 170 extendbetween the mounting anges 30, 32 and the discharge conduit 165 adjacentthe high end of the engine cylinder head and manifold, these conduitsdening small tubular passages 171, 172 connecting the discharge cham.-ber 164 with the liquid coolant jackets or galleries 158, 159 of thecylinder heads 12 and 12a (see FIGURE ll).

The operation of the liquid coolant heating system is such that inwarming up a cold engine, the valve 13) will be closed such that liquidcoolant heated by the cylinder head combustion will be circulated by thepump 120 to the cylinder block 9 from which it is directed by internalpassages to the heads 12, 12a and from there to the heat transfercompartment 34a by the cross inlet conduits 152, 154 and returned to thepum-p by way of the discharge chamber 165,.housing 133 and conduit 134.As previously mentioned, :the hot circulating liquid coolant impingesupon the side walls 108, 109 of the primary airfuel yconduit 52, heatsthe floor 106 of this conduit in illing the compartment, rises in levelin the chamber to heat the surrounding Wall 160 of the riser 48, andleaves by the discharge chamber 164 of the conduit 165. The heattransferred by the hot liquid coolant to the aforesaid wall structuresis transferred to the air-fuel mixture passing through the riser 48 andprimary distribution zone 54. In the event that `air or steam pocketstend to form in the cylinder heads 12 and 12a, the bleed passages 171,17 2 between the cylinder heads and the discharge chamber 164 provide ameans of escape therefor and thus prevent any interruption in the smoothoperation of the engine.

When lthe engine is up to temperature, the valve 130 opens and thegreater portion of the liquid coolant returns to the pump 120 by way ofthe radiator 137. The construction of the air-fuel distribution systemin the modification in FIGURES 6 to l2 `is otherwise the same as thatdiscussed above in connection with the structure of FIG- URE 2.

In FIGURES 13 through 17 inclusive, we have shown our novel XX manifoldconstruction of FIGURE 2 ernbodied in a manifold arrangement 29hproviding for feed of the air-fuel intake system by a double barrelcarburetor and which further differs in utilizing a liquid coolant heattransfer arrangement, the latter materially differing from that employedin the manifold of FIGURE 7 insofar as the manner of `circulating thehot liquid coolant in the manifold itself is concerned. Moreover, thisconstruction incorporates a floor dam for liquid fuel control.

Thus the manifold in FIGURE 13 has opposite mounting flanges 30 and 32similar to those of the manifold of FIGURE 2, and two similar sets ofconduits connected by ya conduit 52a on the axes 2.2 and arranged toform an XX figure, one set or group comprising the similar conduits 63,64, 65, and 66, and the other the similar conduits 67, 68, 69, and 70.As evident from FIGURE 14, all of the conduits 63, 64, 67, and 68 on oneside of the manifold are in the same general elevational plane and thesame is true of fthe conduits 65, 66, 69, and 70 at the opposite side ofthe manifold. Moreover, both sets of conduits lare in the sameelevational plane and in the same elevational plane as the vconduit 52aand preferably have a common floor, generally designated by the numeral174 as seen in FIGURE 16. The manifold 29h is fed by a dual barrelcarburetor 175 mounted on a central rectangular pad 42a and having itsbarrels 176, 177 coinciding with fthe intake riser passages 48a, 48b ofthe manifold, the latter passage being defined by cylindricalsubstantially vertical wall portions 178, 179, 180 which extenddownward-ly from the pad 42a to intersect with the conduit 52a intowhich they open at the primary distribution zone 54a which is the fullwidth of the conduit 52a which in turn has la width suicient toencompass the two riser passages. As seen in FIGURE 13, the air-fuelconduit 52a intersects with the sets of branch conduits forming each Xin further distribution zones 69 and 62 similar to those of FIGURE 2. Itwill be evident that in operation the air-fuel mixture from the risers48a and 48h will be distributed by the primary conduit 52a to thedistribution points 60 and 62 and thence to the branch passages formingeach X. The carburetor may be controlled to have both its barrelsdischarge their air-fuel mixture into the conduit 52a during alloperations of the engine or the barrels may be staged such thatinitially one barrel only will discharge its air-fuel mixture into oneriser, for instance the riser 48a for distribution to' the cylinders andsubsequently Lat a predetermined engine speed or load condition, thesecond barrel will come into play such that both barrels discharge theirair-fuel mixtures into the conduit 52a by their respective risers of themanifold.

It will be noted that the floor 174 is provided in the conduit 52a witha pair of short upstanding transverse ribs or protuberances 180:1 and18017 of the risers 48a and 48b (see FIGURE 13). These ribs form damsfor controlling distribution of the liquid fuel and facilitate best useof the interconnecting conduit 52a for multiple carburetion. The ribs1S9a and 180b of each pair are preferably laterally spaced to provide arecess or gateway 180C for drainage.

Heat transfer to the hot spot comprising the intake risers anddistribution chamber 54a is effected by a liquid coolant heat transfercompartment v181 which jackets the risers 48a, 48h, and conduit 52a andgenerally comprises a U-shaped chamber generally referred to by thenumeral 182 and best seen in FIGURE 15 which jackets the conduit 52a-transversely over its full length and which includes a left side legportion 183, a base portion 184, and upper and lower right leg portions1-85a, 185b divided by a floor 186. In addition, rectangular passagesl87a, 187b on opposite sides of the intake risers 48a, 48h interconnectthe upper end of leg portion 183 with the leg portion 185:1. The hotliquid coolant for the compartment 181, chamber -182 enters the manifoldat its forward or high end through cylindrical apertures 188, 1-89 inthe mounting anges 3G and 32 respectively (see FIGURE 17) from waterpassages '190, 191 in the cylinder heads 12 and 12a. As seen in FIGURES13 and 17, suitable conduits 192, 193 extend from the flanges 30, 32respectively to connect with the hot spot compartment 181. It will beevident from FIGURE 17 that the conduit 192 comprises a transverselyextending horizontal passage portion 194 of generally rectangular shapelocated intermediate the air-fuel conduits 65, 66 corresponding to thecylinders 1 and 3 of the engine and starting at the aperture 188, thispassage turning rearwardly and downwardly at the position 195 andconnecting with a short somewhat flattened rectangular passage -196having a cross sectional area substantially that of the passage 194, thepassage 196 in turn connecting with the base portion 184 of the chamber182 by an inlet 197.

The inlet conduit 193 has a similar but opposite passage system to thatof the conduit 192 it providing a transversely extending passage 198which turns downwardly and rearwardly at the position 199 and connectswith the base 184 of the U chamber 182 of the compartment 180 by aflattened rectangular passage 200 opening into the bottom portion 184 ofthe U chamber by an aperture 201 as seen in FIGURE 15.

The hot liquid coolant entering the compartment 181 from the conduits192 and 193 will fill the U-shaped chamber 182 thereof, the hot liquidcoolant rising first in the base 184 and leg portions 183 and 185b andthrough an aperture 202 of the floor 186 in the leg 185a and flowingaround the intake risers by way of the passages 183:1, 18311 of whichthe riser walls 178, 179 form a part. The liquid coolant after rising inthe chamber 182 discharges at the right side of the manifoldintermediate the air-fuel conduits 64, 68 for the cylinders 4 and 6 bymeans of a conduit 206 providing a passage 207 which connects with theleg 185a and with the leg 185b through aperture 202 of the chamber 182,and which passage 207 extends transversely of the manifold and upwardlyat a portion 208 provided by a wall portion 209 connecting with themounting flange 32 and terminates in an aperture 210 above the level ofthe legs 183, 185a of chamber 182 in a seat or pad 211 arranged toreceive a hose connection (not shown) in turn connecting with the casing133 of the control valve 130 shown schematically in FIGURE 6, forcirculation tothe return side of the pump during warm-up and to theradiator 137 during normal operation of the engine following warm-up, itbeing understood that a similar liquid coolant delivery and returnsystem is used in connection with the manifold of 'FIGURE 13 as thatillustrated in FIGURE 6, the thermostatic valve and its casing 133 inthe case of the FIGURE 13 manifold being generally located adjacent theradiator 137.

In order to provide for drainage of liquid coolant from the manifold29!) for engine storage, a drain passage 215 closed by a plug 216 isprovided below the air-fuel conduits and connects with the base portion184 of the chamber 182.

It will be evident from FIGURES 15 and 16 that the hot liquid coolantwill transfer heat to the walls 215, 216, 217, 218, 219 of the conduit52a as well as the walls 178, 179, of the riser passages 48a and 48b soas to transfer heat to the air-fuel mixture flowing in the risers 48a,48b and the conduit 52a during warm-up of the engine. It will be evidentthat with the arrangement in FIG- URE 13 any air or steam trapped in thecylinder heads 12, 12a may readily escape by Way of the conduits 1.92,193 and the discharge conduit 206.

In FIGURES 18 and 19, We have schematically shown further modificationsof intake manifolds for V-8 engines applying our XX manifoldconstruction. The manifold in FIGURE 18 provides for the mounting of apair of single barrel carburetors (not shown) one at the intersection ofthe air-fuel conduits of each X of the manifold immediately above thedistribution zones 60, 62 respectively. The manifold in FIGURE 19illustrates how our invention may be applied to a manifold mountingthree in-line single barrel carburetors (not shown). Each of themanifolds in FIGURES 18 and 19, as in the case of that in FIGURE 5 isshown to utilize the exhaust gases of the engine for heating the riserhot spot of the intake system, the modification in FIGURE 18 disclosingan arrangement for conducting hot exhaust gases to each riser and thatin FIGURE -19 merely disclosing the heating of the central carburetorriser. It will be understood that the liquid coolant heating features ofFIGURES 7 and 13 are also applicable to these modifications.

Referring now more particularly to FIGURE 18, it will be observed thatthe riser 220 directly connects with the distribution Zone 62 formed atthe intersection of the conduits 67, 68, 69, and 70 and that the riser222 connects with the distribution zone 60 of the intersecting airfuelconduits 63, 64, 65, 66. -In order to improve the air-fuel distributionto the individual cylinders and obtain as nearly equal fuel-air ratiosas possible at the individual cylinders, the intake risers 220 and 222are interconnected by a conduit or tube 226, preferably in the plane ofthe conduits. To provide for heating of the riser passage and primarydistribution zone during warm-up of the engine, a compartment 230jackets the intersecting portions of the conduits 67, `68, 69, and 70 aswell as the riser Wall portion 232 and a portion of the connecting tube226 and a similar compartment 236 jackets the intersecting portions ofthe conduits 63, 64, 65, and 66, the wall portion 238 of the riser 222and the adjacent connecting portion of the tube 226. Hot exhaust gasesare provided to the manifold in the manner described with respect to thearrangement in FIGURE by the cylinder head exhaust crossover passages105, 105a which connect with transverse conduits 240, 242 of themanifold extending transversely of the engine intermediate the cylinders3 and 5 of the left hand bank, and cylinders 4 and 6 of the right handbank respectively. As seen in FIGURE 18, the conduit 240 connects withthe compartments 230 and 236 respectively by branch conduits 244, 246and that the conduit 242 similarly connects with the compartments 230and 236 by branch conduits 248, 250. During engine Warm-up the hotexhaust gases from the right hand cylinder bank Will move through theconduit 242 to the compartments 230 and 236 to heat the wall portions ofthe air-fuel system surrounded by these compartments and transfer heatto the air-fuel mixture and will leave by the conduit 240 and crosspassage 105 for discharge into the exhaust manifold 96 of the left handbank of the engine as previously described in connection with thearrangement in FIGURE 5.

Referring now to FIGURE 19, this modification is provided with theintake riser passages 220 and 222, as in FIGURE 18, and with a thirdintake riser passage 260 formed by a cylindrical wall 262 and the lowerend of which passage 260 is closed. Suitable conduits or tubes 270, 272in the plane of the conduits interconnect the pairs of risers 220 and260 and 260 and 222 respectively. It will be evident that the carburetordischarging into the riser 260 will have its air-fuel mixture deliveredby the tubes 270, 272 to the risers 220 iand 222 respectively toincrease the amount of air-fuel mixture delivered to the distributionareas 60, 62 of the X formations of the manifold. It will be understoodthat the carburetors feeding this manifold may be staged such thatinitial operations of the engine commence with the carburetor feedingthe riser 260 and that at a given speed or load of the engine, thecarburetors feeding the risers 220 and 222 may be cut in to supplementthe engine air-fuel feeding or conversely the carburetors feeding therisers 220, 222 may be cut in rst and that feeding the riser 260 cut inlater.

Heating of the air-fuel mixture during engine warm-up is provided inthis modification in a manner similar to that in FIGURE 5 by providing achamber 280 jacketing the manifold intake riser 260 and portions of theconnecting tubes 270 and 272, this chamber 280 connecting by means ofthe transverse conduits 282, 284 extending intermediate the cylinders 3and 5 of the left hand bank, and 4 and 6 of the right hand bank with theexhaust gas crossover passages 105, 10511 of the cylinder heads 12 and12a as previously described in connection with the arrangement in FIGURE5.

From the foregoing description of our invention, it will be apparentthat we have provided a novel and simple intake manifold for V engineshaving an XX formation and which is adapted to many different enginefeeding arrangements and is capable of assuring excellent performance ofthe engines of which it is a part. It will Hence these and all otherYchanges 12 and modifications and equivalent structures coming withinthe purview of our invention are contemplated.

We claim:

1. An intake manifold for a multicylinder engine having oppositecylinder heads, each of which is provided with a mounting face for saidmanifold, a liquid coolant gallery, passage means connecting saidgallery with said mounting face, and air-fuel mixture delivery passagesbetween said mounting face and the intake valve ports of the cylinders;said manifold comprising opposite ange portions for mounting saidmanifold to the said mounting faces of said cylinder heads, `a singlepassage central air-fuel conduit having air-fuel riser means, coplanargroups of branch air-fuel conduits connecting with each end of saidcentral conduit and in susbtantially the plane thereof, each of saidgroups arranged in the form of a letter X and having their connectionwith said central conduit at the intersection of the branch conduits ofsuch groups, said branch conduits defining passages for conductingair-fuel mixture to said delivery passages of said heads, a liquidcoolant compartment jacketing said central conduit at said riser means,liquid coolant intake conduit means extending transversely of saidmanifold between said compartment and said opposite mounting portionsand defining passages connecting said compartment with certain of saidpassage means of said galleries at said mounting faces, liquid coolantreturn conduit means extending longitudinally of said manifold from saidcompartment to adjacent one end thereof and defining passage means forconducting liquid coolant from said compartment, and bleed conduit meansextending transversely of said manifold between said return conduitmeans and said mounting portions and defining passage means connectingsaid liquid coolant return passage means with other of said passagemeans of said galleries at said mounting faces.

2. An intake manifold for a multicylinder engine having oppositecylinder heads, each of which is provided with a mounting face for saidmanifold, a liquid coolant gallery, passage means connecting saidgallery with said mounting face, and air-fuel mixture delivery passagesbetween said mounting face and the intake valve ports of the cylinders;said manifold comprising opposite flange portions for mounting saidmanifold to the said mounting faces of said cylinder heads, a singlepassage longitudinally extending central air-fuel conduit having airfuelriser means, coplanar groups of branch air-fuel conduits connecting witheach end of said central conduit and in substantially the plane thereof,each of said groups arranged in the form of a letter X and having theirconnection with said central conduit at the intersection of the branchconduits of such groups, said branch conduits defining passages forconducting air-fuel mixture to said delivery passages of said heads, aliquid coolant compartment jacketing said central conduit at said risermeans, liquid coolant intake conduit means extending transversely ofsaid manifold between said opposite mounting portions and one end ofsaid compartment longitudinally of said manifold and defining passagesconnecting said compartment with certain of said passage means of saidgalleries at said mounting faces, liquid coolant return conduit meansextending transversely of said manifold ybetween a side of saidcompartment and a mounting flange portion of said manifold and definingpassage means for conducting liquid cool-ant from said compartment tothe top side of said manifold.

3. An intake manifold for a multicylinder engine having oppositecylinder heads, each of which is provided with a mounting face for saidmanifold, a liquid coolant gallery, passage means connecting saidgallery with said mounting face, andtair-fuel mixture delivery passagesbetween said mounting face and the intake valve ports of the cylinders;said manifold comprising opposite flange portions for mounting saidmanifold to the said mounting faces of said cylinder heads, a centrallongitudinally extending single passage air-fuel conduit having a pairof transversely arranged air-fuel riser means connecting therewith,coplanar groups lof branch air-fuel conduits connecting with each end ofsaid central conduit and with said flange portions and being insubstantially the plane of said central conduit, each of said groupsarranged in the form of -a letter X and having their connection withsaid central conduit at the intersection of the branch conduits of suchgroups, said branch conduits dening passages for conducting air-fuelmixture to said delivery passages of said heads, la liquid coolantcompartment jacketing said central conduit at said riser means, liquidcoolant intake conduit means extending transversely of said manifoldbetween said opposite mounting portions and one end of said compartmentand defining passages connecting said compartment with certain `of saidpassage means of said galleries at said mounting faces, liquid coolantreturn conduit means extending transversely of said manifold between aside of said compartment and a mounting flange portion of said manifoldand defining passage means for conducting liquid coolant from saidcompartment to the top vside of said manifold.

4. An intake manifold for a multicylinder engine having oppositecylinder heads each of which is provided with a mounting face for saidmanifold, an exhaust gas cross-over passage, and air-fuel mixturedelivery passages between said mounting face and the intake valve portsof the cylinders; said manifold comprising opposite flange portions formounting said manifold to said mounting faces of the cylinder heads, acentral longitudinally extending -air-fuel conduit, coplanar groups ofbranch airfuel conduits connecting with each end of said central conduitand with said mounting flanges and being substantially in the plane ofsaid central conduit, each of said groups arranged in the for-m of aletter X and having their connection with said central conduit at theintersection of the branch conduits of such groups, said ybranchconduits defining passages for conducting air-fuel mixture to saiddelivery passages of said heads and there being only one of said groupsof branch conduits having one of its passages connecting with any onedelivery passage of said heads, an air-fuel intake riser at theintersection of the branch conduits of each group and a further intakeriser intermediate the ends of said central air-fuel conduit, a heatingcompartment jacketing a portion of said central conduit at said intakeriser thereof, and transverse heating conduit means connecting oppositesides of said compartment with the angc portions of said manifold atsaid sides, said transverse heating conduit means terminating inopenings in said flange portions which openings are adapted to coincidewith the inlets of said exhaust crossover passages of said cylinderheads.

5. An intake manifold for V engines comprising a primary distributionconduit having opposite ends, la fuel intake port opening into the topside of said conduit intermediate said ends, a plurality of branchconduits connecting with each end of said primary conduit, said primaryand vbranch conduits having bottom oors substantially in the samehorizontal plane, and a shallow fuel dam on the'floor of said primaryconduit below said fuel intake port.

6. An intake manifold for a V engine comprising a unitary structureincluding a longitudinally extending generally horizontal distributionconduit, said conduit having opposite ends, a fuel intake riser openinginto the top side of said conduit for facilitating the delivery of fuelthereto, wall means defining a distribution zone adjacent each of saidconduit ends and connecting therewith, said zones being substantiallycoplanar with said conduit and having their top and bottom wallsdefining part of the top and bottom surfaces respectively of saidmanifold, and a separate group of elongated branch conduits connectingwith each of said distribution zones and extending transverselytherefrom substantially in the plane of said zones to terminal `openingsadjacent the sides of said manifold, each of said terminal openingsadapted to register with theintake passage of a different cylinder andeach of said branch conduits having a length greater than its width.

7. An intake manifold for Va V engine comprising a unitary structureincluding a longitudinally extending generally horizontal distributionconduit, said conduit having opposite ends, a fuel intake riser openinginto the top side of said conduit for facilitating the delivery of fuelthereto, wall means defining a distribution zone adjacent each of saidconduit ends and connecting therewith, said zones being substantiallycoplanar with said conduit and having their top and bottom wallsdefining part of the top and bottom surfaces respectively of saidmanifold, and a separate group of elongated branch conduits connectingwith each of said distribution zones and extending transverselytherefrom substantially in the plane of said zones to terminal openingsadjacent the sides of said manifold, each of said terminal openingsadapted to register with the intake passage of a different cylinder, thesaid conduits of each of said group of elongated branch conduitssimulating legs of a letter X with their connecting distribution zone.

8. An intake manifold for a V engine comprising a unitary structureincluding a longitudinally extending generally horizontal distributionconduit, said conduit having opposite ends, a fuel intake riser openinginto the top side of said conduit for facilitating the delivery of fuelthereto, wall means defining a distribution zone adjacent each of saidconduit ends and connecting therewith, said yzones being substantiallycoplanar with said conduit and having ther top and bottom walls deningpart of the top and bottom surfaces respectively if said manifold, and aseparate group of elongated branch conduits connecting with each of saiddistribution zones and extending transversely therefrom in the plane ofsaid zones to terminal openings adjacent the sides of said manifold,each of said terminal openings adapted to register with the intakepassage of a different cylinder, said groups of branch conduitssimulating a letter X in arrangement, and each of said branch conduitshaving a length greater than its width.

9. An intake manifold for a V engine comprising a unitary structureincluding opposite mounting anges, a longitudinally extending generallyhorizontal distribution conduit, said conduit having opposite ends, afuel intake riser opening into the top side of said conduit forfacilitating the delivery of fuel thereto, wall means defining adistribution zone adjacent each of said ends of said distributionconduit and connecting therewith, said zones being substantiallycoplanar with said conduit and having their top and bottom wallsdefining part of the top and bottom surfaces respectively of saidmanifold, and a separate group of elongated branch conduits connectingwith each of said distribution zones and extending transverselyItherefrom substantially in the plane of said zones to terminal openingsin said mounting anges, each terminal opening being adapted to registerwith the intake passage of a different cylinder, each of said groups ofbranch conduits simulating a letter X with its connecting distributionzone and half of said branch conduits of each group connecting withterminal openings in one mounting flange and half connecting withterminal openings in the other mounting ange.

l0. An intake manifold for a V engine comprising a unitary structureincluding opposite mounting flanges, a longitudinally extendinggenerally horizontal distribution conduit, said conduit having oppositeends, wall means defining a distribution zone adjacent each of said endsof said distribution conduit and connecting therewith, said zones beingsubstantially coplanar with said conduit and having their top and bottomwalls defining port of the top and bottom surfaces respectively of saidmanifold, a separate group of elongated branch conduits connecting witheach of said distribution zones and extending transversely therefromsubstantially in the plane of said zones to terminal openings in saidmounting anges, each terminal opening being adapted to register with theintake passage of a different cylinder, fuel intake riser means openinginto each of said distribution zones through the said top wall thereofand each of said branch conduits having a length greater than its width.

11. An intake manifold for a V engine comprising a unitary structureincluding opposite longitudinally extending mounting flanges, aplurality of groups of substantially coplanar elongated conduitsinterconnecting with said ange portions and defining passages havingapertures in said flange portions adapted for registration With theintake passages of different cylinders of said engine, a longitudinallyextending horizontal distribution conduit in substantially the sameplane as said groups of conduits and having opposite ends, Wall meansdening a distribution zone adjacent each of said ends of saiddistribution conduit and connecting with that end to which it isadjacent and connecting with the conduits forming one of said groups ofconduits at the intersection of the conduits forming such group, each ofsaid groups of branch conduits simulating a letter X with its connectingdistribution zone and said distribution zones having their top andbottom Walls defining part of the top and bottom surfaces respectivelyof said manifold, and fuel intake riser means extending through the topsurface of said manifold and opening into at least one of saiddistribution conduit end zones.

l2. An intake manifold for a V engine comprising a unitary structureincluding opposite mounting flange portions, a longitudinally extendinggenerally horizontal distribution conduit, said conduit having oppositeends, Wall means defining a distribution zone adjacent each of said endsof said distribution conduit and connecting therewith, said zones beingsubstantially coplanar with said conduit and having their top and bottomwall dening part of the top and bottom surfaces respectively of saidmanifold, a separate group of elongated branch conduits connecting witheach of said distribution zones and extending transversely therefromsubstantially in the plane of said zones to terminal openings in saidmounting anges, each terminal opening being adapted to register with'theintake passage of a cylinder and there being only one of said conduitsconnecting with any one intake passage of said engine, each of saidgroups of branch conduits simulating a letter X with its connecting`zone with half of said branch conduits of each group connecting withone mounting tiange portion and half connecting with the other mountingflange portion and there being fuel intake riser means opening throughthe top Wall of each of saidtdistribution zones for supplying fuelthereto.

13. An intake manifold for a V-engine comprising a unitary structureincluding opposite mounting flange portions, a longitudinally extendinggenerally horizontal distribution conduit, said conduit having oppositeends, wall means defining a distribution zone adjacent each of said endsof said distribution contduit and connecting therewith, said zones beingsubstantially coplanar with said conduit and having their top and bottomwalls defining part of the top and bottom surfaces respectively of saidmanifold, fuel intake riser means on said manifold for supplying fuel tosaid distribution zones, a separate group of elongated branch conduitsconnecting with each of said kdistribution zones and extendingtransversely therefrom substantially in the plane of said zones toterminal openings in said mounting Harige portions, each terminalopening being adapted to register with the intake passage of a differentcylinder, each of said groups of branch conduits simulating a letter Xand those conduits forming opposite legs of said letter X being insubstantial alignment.

14. An intake manifold for a V engine comprising a unitary structureincluding'opposite mounting flange por- 1'6 tions, a longitudinallyextending generally horizontal distribution conduit, said conduit havingopposite ends, Wall means defining a distribution zone adjacent each ofsaid ends of said distribution conduit and connecting therewith, saidzones being substantially coplanar with said conduit and having theirtop and bottom Walls deiining part of the top and bottom surfacesrespectively of said manifold, fuel intake riser means opening, intoeach of said distribution zones, and a separate group of elongatedbrauch conduits connecting with each of said distribution zones .andextending transversely therefrom substantially in the plane of saidzones to terminal openings in said mounting ange portions, each terminalopening being adapted to register with the intake passage of a differentcylinder, each of said groups of branch conduits simulating a letter Xand those conduits formingopposite legs of said letter X being insubstantial alignment.

15. An intake manifold for a V engine comprising a unitary structureincluding opposite mounting ange portions, a longitudinally extendinggenerally horizontal distribution conduit, said conduit having oppositeends, a plurality of fuel intake risers opening into saidY conduitintermediate said ends, the said conduit providing a common conduit forsaid risers, wall means defining a distribution zone adjacent each ofsaid ends of said distribution conduit and connecting therewith, saidzones being substantially coplanar with said conduit and having theirtop and bottom walls defining part of the top and bottom surfacesrespectively of said manfold, the said distribution zones receiving fuelonly through said distribution conduit, a separate group of elongatedbranch conduits connecting with each of said distribution zones andextending transversely therefrom substantially in the plane of saidzones to terminal openings in said mounting iiange portions, eachterminal opening being adapted to register with the intake passage of adifferent cylinder and there being only one conduit of said groups ofbranch conduits connecting with any one intake passage of said engine,each of said groups of branch conduits simulating a letter X with itsconnecting distribution zone and half of said branch conduits of eachgroup connecting with one mounting flange portion and half connectingwith the other mounting flange portion. l

16. An intake manifold for a V engine comprising a unitary structureincluding opposite mounting flange portions extending longitudinally ofsaid manifold, a longitudinally extending generally horizontaldistribution conduit, said conduit having opposite ends, fuel risermeans opening into the top side of said distribution conduit for'facilitating a delivery of fuel thereto, Wall means defining adistribution zone adjacent each of said ends only of said distributionconduit and connecting therewith, said zones being substantiallycoplanar with said conduit and having their top and bottom Wallsdefining part of the top and bottom surfaces respectively of saidmanifold, a separate group of elongated branch conduits connecting witheach of said distribution zones and extending transversely therefromsubstantially in the plane of said zones to terminal openings in saidmounting flange portions, each terminal opening being adapted toregister with the intake passage of a different cylinder, each .of saidgroups of branch conduits simulating a letter X with its connectingdistribution zone with half of said branch conduits of each groupconnecting with one mounting flange portion and half connecting with theother mounting iiange portion, and a heating compartment defined in partby said distribution conduit and riser means and in part by Wall meansspaced from said distribution conduit for providing a heat exchange zonefor fuel passing through said distribution conduit.

17. An intake manifold for a multi-cylinder engine having oppositecylinder heads, each of which is provided with a mounting face for saidmanifold, a passage for conducting a fluid heating medium to saidmanifold and air fuel mixture delivery passages between said mountingfac@ @11d .the intake valve ports of the cylinders; said 17y manifoldcomprising opposite mounting flange portions for mounting said manifoldto said mounting faces, of said cylinder heads, a single generallycentral longitudinally extending generally horizontaldistributionconduit having opposite ends, wall means defining adistribution zone adjacent each of said ends of said distributionconduit and connecting therewith, said zones being substantiallycoplanar with said distribution conduit and having theirV top and bottomwalls defining part of the top and bottom surfaces respectively of saidmanifold, a separate group of elongated branch lconduits connecting witheach Aof said distribution zones' and extending transversely therefromsubstantially in the plane of said zones to terminal openings in saidmounting ange portions, each of said branch conduits connecting throughits said terminal opening with a different air fuel mixture deliverypassage of said heads, each of said groups of branch conduits simulatinga letter X with its connecting zone and having half of its said branchconduits connecting with one mounting flange portion and half connectingwith the other mounting ange portion, heat transfer compartment meansjacketing the sides and bottom portion of said distribution conduit andconduit means connecting opposite sides of said compartment means withthe mounting ange portion of said manifold nearest thereto, said lastmentioned conduit means terminating in openings in the said flangeportions adapted to connect with the said uid passages of said heads.

18. An intake manifold for a multi-cylinder engine having oppositecylinder heads, each of which is provided with a mounting face for saidmanifold, uid heat supply passages, and air fuel mixture deliverypassages between said mounting face and the intake valve parts of thecylinders; said manifold comprising opposite ange portions for mountingsaid manifold to said mounting faces of said cylinder heads, a singlecentral longitudinally extending generally horizontal distributionconduit having opposite ends, Wall means dening a distribution zoneadjacent each of said ends of said distribution conduit and connectingtherewith, said zones being substantially coplanar with said conduit andhaving their top and bottom walls dening part of the top and bottomsurface respectively of said manifold, a separate group of elongatedbranch conduits connecting with each of said distribution zones andextending transversely therefrom substantially in the plane of saidzones to terminal openings in said mounting anges, each terminal openingbeing adapted to register with the intake passage of a differentcylinder, each of said groups of branch conduits simulating a letter Xwith its said connecting zone and having half of its said branchconduits connecting with one mounting ange portion and half connectingwith the other mounting flange portion, air fuel intake riser meansopening through the said top wall of said distribution zones adjacentthe intersection of said groups of branch conduits with said zones, aheat exchange compartment jacketing each of said distribution zones atsaid riser means and uid heat conduit means extending from each flangeportion of said manifold and connecting with each of said heat transfercompartments, said heat conducting conduits having apertures in saidflange portions of the manifold adapted to connect with the said heatsupply means of said heads.

19. An intake manifold for a multi-cylinder engine having oppositecylinder heads, each of which is provided with a mounting face for saidmanifold, an exhaust gas crossover passage, and air fuel mixturedelivery passages between said mounting face and the intake valve portsof the cylinders; said manifold comprising opposite flange portions formounting said manifold to said mounting faces of said cylinder heads, asingle longitudinally extending generally horizontal distributionconduit having opposite ends, Wall means defining a distribution zoneadjacent each of said ends of said distribution conduit and connectingtherewith, said zones being substantially coplanar with saiddistribution conduit and having their top and bottom Walls defining partof the top and bottom surgroups of branch conduits simulating a letter Xwith its connecting zone and having half of its branch conduitsconnecting with one mounting flange portion `and half connecting withthe other mounting flange portion, each of said branch conduits having aterminal opening in said mounting flange connecting with a different airfuel mixture delivery passage of said engine, intake riser means openingthrough the said top wall of each of said distribution zones forsupplying fuel to said branch conduit, a heating compartment jacketingeach of the intersections of said riser means and distribution zone andconduit means extending from each flange portion of said mani- -fold andhaving branches connecting with each of said heating compartments, saidheating conduit means having apertures in said ange portions of themanifold adapted to connect with said exhaust gas crossover passages ofsaid cylinder heads.

20. An intake manifold for V engines comprising a primary distributionconduit having opposite ends, a fuel intake port opening into saidconduit intermediate said ends, a plurality of branch conduitsconnecting with each end of said primary conduit, said primary andbranch conduits having bottom floors substantially in the samehorizontal plane, a shallow fuel dam on the floor of said primaryconduit adjacent said fuel intake port, and a recess in said damproviding for fuel drainage therefrom.

21.V An intake manifold for a multi-cylinder engine having oppositecylinder heads comprising a unitary structure including oppositemounting flange portions, a longitudinally extending generallyhorizontal distribution conduit, said conduit having opposite ends, wallmeans delining a distribution zone adjacent each of said ends of saiddistribution conduit and connecting therewith, said zone beingsubstantially coplanar with said conduit and having their top and bottomwalls defining part of the top and bottom surfaces respectively of saidmanifold, a separate group of elongated branch conduits connecting withVeach of said distribution zones and extending transversely therefrom inthe plane of said zones to terminal openings in said mounting flanges,each terminal opening being adapted to register with the intake passageof a different cylinder, each of said groups of branch conduitssimulating a letter X with its connecting zone and having half of itssaid branch conduits connecting with one mounting flange portion andhalf connecting with the other mounting flange portion, an air fuelintake riser adjacent the intersection of the branch conduits of eachgroup and its said distribution zone, and a further intake riserintermediate the ends of said distribution conduit, heat transfercompartment means jacketing a portion of said distribution conduit atits said intake riser thereof and uid heat conduit means connectingopposite sides of said compartment with the ange portions of saidmanifold, said uid heat conduit means terminating in openings in saidflange mounting portions which openings are adapted to coincide with uidheat supply passage means in the cylinder heads of said engine.

22. An intake manifold for a multi-cylinder engine having oppositecylinder heads, each of which is provided with a mounting face for saidmanifold, a liquid coolant gallery, passage means connecting saidgallery with said mounting face, and air fuel mixture delivery passagesbetween said mounting face and the intake valve ports of the cylinders;said manifold comprising opposite ange portions for mounting saidmanifold to the said mounting faces of said cylinder heads, a centralair fuel conduit having air fuel riser means, coplanar groups ofelongated branch air fuel conduits connecting with each end of saidcentral conduit and in substantially the plane thereof, each of saidgroups of conduits arranged in the form of a letter X and having theirconnection -with said central conduit at a distribution zone situated atthe intersection of the branch conduits of such groups, said branchconduits defining passages for conducting air fuel mixture to saiddelivery passages of said heads, a liquid coolant compartment jacketingthe central conduit at said riser means, liquid ycoolant conduit meansextending transversely of said manifold ibetween said manifold mountingportion and said compartment, and adjacent one end of said compartmentlongitudinally of said manifold and further liquid coolant conduit meansextending transversely of said manifold between said compartment andsaid mounting portion of said manifold and spaced longitudinally of themanifold from said iirst mentioned liquid coolant conduit means, certainofV said liquid conduit means connecting with'said gallery passagemeans.

v23. In an engine having a cooling system containing a coolant in heatabsorbing relation with said engine and a heat exchanger for dissipatingthe heat absorbed by said coolant, the combination of an intake manifoldhaving distribution passages therein, a jacket in said manifold forplacing said coolant in heat exchanging -relation with Said distributionpassages, connecting'means for interconnecting said jacket with saidcooling system and with said heat exchanger, said connecting meansincluding valve means movable between two positions, said valve meanswhen in one of said positions directing the ow of coolants from saidcooling system into said jacket and when Vin the other of said positionsdirecting the flow of coolants from said cooling system into said heatexchanger, thermostatic means for moving said valve means from one ofsaid positions to the other of said positions in response to thetemperature of said coolant.

24. An intake manifold for a V-type internal combustion engine havingangularly disposed banks of cylinders, said manifold comprising a memberhaving a longitudinally extending distribution passage and transverselyextending branch passages having the centers thereof communicating withthe opposite ends of said distribution passage, the opposite ends ofsaid branch passages forming ports in the sides of said manifold tocommunicate with individual cylinders, a primary carburetor riserdisposed in the center of said member and having a primary chargesupplying passage intersecting the center of said distribution passagefor supplying a combustible charge during all phases of operation,secondary carburetor risers disposed remote from'said iirst riser andhaving secondary Vcharge supplying passages communicating with thejunctions of the distribution and the branch pasages for supplyingsecondary charges thereto during certain operating conditions.V

25. An intake manifold Vfor a V-type internal combustion engine havingangularly disposed banks of cylinders, said manifold comprising a memberhaving a longitudinally extending distribution passage and a pair oftransversely extending branch passages having the centers thereofinterconnected with the opposite ends of said distribution passage, theopposite ends of said branch passages forming ports in the sides of saidmanifold to communicate with individual cylinders, a primary carburetorriser disposed in the center of said member and having a primary chargesupplying passage intersecting the'center of` said distribution passage-for supplying a combustible charge during all phases of operation,secondary carburetor risers disposed remote from said first riser Vandhaving secondary charge supplying passages communicating with thejunctions of the distribution and 'the branch passages for supplyingsecondary combustible charges thereto only during certain operatingconditions, means for heating the portion of said distribution passageadjacent the intersection of said primary charge supplying passage andsaid distribution passage.

References Cited in the tile of this patent UNITED STATES PATENTS2,012,902v Barkeij Aug. 27, 1935 2,098,424 Kolimbat Nov. 9, 19372,124,403 McIntyre July 19, 1938 2,260,309 Funderburk Oct. 28, 19412,603,199 Moseley July 15, 1952 2,686,506 Carpentier et al. Aug. 17,1954 FOREIGN PATENTS 515,410 Great Britain Feb. 28, 1938 834,158 FranceAug. 8, 1938

